1. Field of the Invention
This invention relates to a camera and to a method of controlling the operation thereof.
2. Description of the Related Art
An optical/electronic viewfinder that can be switched between an optical viewfinder and an electronic viewfinder is available in the art. In a case where an optical/electronic viewfinder functions as an optical viewfinder, the user can see the optical image of a subject through an objective window, which is formed on the front of the camera, when the user looks at the subject through an eyepiece window. In a case where the optical/electronic viewfinder functions as an electronic viewfinder, the image of a subject obtained by imaging is displayed on a liquid crystal panel and this image is introduced to the eyepiece window by a deflecting device such as a half-mirror and prism or the like. The user looking at the eyepiece window sees the image of the subject being displayed on the liquid crystal panel (Patent Document 1).
The optical/electronic viewfinder is provided with a finder shutter between the deflecting device and the objective window. If a changeover is made from the optical viewfinder to the electronic viewfinder, the finder shutter closes. As a result, the eye of the user looking at the eyepiece window cannot see the subject through the objective window and see the image of the subject displayed on the liquid crystal panel. Conversely, if a changeover is made from the electronic viewfinder to the optical viewfinder, the finder shutter opens and the image of the subject being displayed on the liquid crystal panel vanishes.
In addition to a digital single-lens reflex camera having the above-described optical/electronic viewfinder, there is also one having an electronic viewfinder that shares part of the optical system of an optical viewfinder and makes it possible to observe an electronic image captured by imaging means (Patent Document 2). There is also a single-lens reflex camera that can be switched between observation of a subject from an optical finder and observation of a subject achieved by displaying the image of the subject on a back panel (Patent Document 3). There are other examples as well.
Patent Document 1: Japanese Patent Application Laid-Open No. 2012-63722
Patent Document 2: Japanese Patent Application Laid-Open No. 2008-60811
Patent Document 3: Japanese Patent Application Laid-Open No. 2008-170872
In a case where a changeover is made from the optical viewfinder to the electronic viewfinder in an optical/electronic viewfinder, the interior of the finder suddenly goes dark when the finder shutter suddenly closes. Further, in a case where a changeover is made from the electronic viewfinder to the optical viewfinder, the interior of the finder brightens suddenly when the finder shutter opens. Further, when the image in the electronic viewfinder and the image in the optical viewfinder are superimposed and displayed, a dual image appears and the result will be too bright for the user. When the dual image changes to the image in the electronic viewfinder or to the image in the optical viewfinder, the too-bright image becomes an image that is relatively dark, causing the user to experience flickering. In any case, the user looking at the eyepiece window will experience a sense of incongruity.